For moderately sized molecules, low resolution microwave spectroscopy can determine the number of rotational isomers, their conformation and their relative energies. We recently discovered that it can also provide direct information about barrier heights to internal rotation for relative low barriers (Less than 2 kcal/mol). We propose low resolution microwave studies of substituted amides in order to determine internal rotation potential functions about the peptide bond and the bonds immediately adjacent to it. In some cases, complementary gas phase NMR experiments will aid in determining conformational equilibria and barrier heights.